A Note on the Convexity Radius of the Sphere Sn(1)
Wu Fa'en
Abstract：W. Klingenberg had announced that the convexity radius of the sphere Sn(1) is R=(π)/(2), but he gave no proof. From a more general theorem of J.H.C.Whitehead, one can also come to the same conclusion. We present here a different from J.H.C.Whitehead but elementary (without use of Jacobi fields) proof of this result.
Keywords：normal coordinate eigenvalue positive definite convexity radius
Publication Date：1998-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)